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Finding the Fourth Proportional to 660.96, 990.09 and 386.24

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Solution

The fourth proportional to 660.96, 990.09 and 386.24 is: 578.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.96 : 990.09 = 386.24 : x
  2. Step 2: Convert to fraction form
    660.96/990.09 = 386.24/x
  3. Step 3: Cross multiply
    660.96x = 990.09 × 386.24
  4. Step 4: Simplify right side
    660.96x = 382,407.41
  5. Step 5: Solve for x
    x = 382,407.41/660.96
  6. Step 6: Final answer
    x = 578.56

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.